Buttonhole sewing machine



Nov. 20, 1934. J. H. PIKUL BUTTONHOLE SEWING MACHINE.

3 Sheets-Sheet 1 Filed Jan. 26, 1934 1 \nvenTor. doseph H. P1KU| WW;

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Nov. 20, 1934. .1. 1-1. PlKUL BUTTONHOLE SEWING MACHINE Fild Jan. 26,1934 3 Sheets-Sheet 2 lnvenTor.

\Josepn H. PiKul byMM&f A'H'ys.

NOV. 20, 1934. J PIKUL 1,981,119

BUTTONHOLE SEWING MACHINE Filed Jan. 26, 1934' 5 Sheets-Sheet 3lnven'for.

\Joseph H. PIKUI b faWWkW AITys.

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Patented Nov. 20, 1934 UNITED STATES BUTTONHOLE SEWING MACHINE Joseph H.Pikul, Boston, Mass, assignor to The Reece Button Hole Machine Company,Boston, Mass., a corporation of Maine Application January 26, 1934,Serial No. 708,414

11 Claims.

This invention relates to buttonhole sewing machines and it has for oneof its objects to provide improvements in buttonhole sewing machines bywhich the machine is brought to rest at the end of any buttonhole sewingcycle with the work in a favorable position, as regards the needle, forremoval from the work-holding means Without danger of becoming caught onthe needle. In other words, one of the purposes of the invention is toprovide a novel construction in which, when the sewing machine comes torest at the end of a buttonhole sewing cycle, the work-holding means andthe stitch-forming mechanism are in such relative position that the workcan be readily removed from the clamps without requiring any particularcare on the part of the operator to prevent the work from catching onthe raised needle.

Another object of the invention is to provide improvements by which thetime involved in completing any buttonhole sewing cycle may be reducedwithout actually increasing the speed of operation of the stitchformingmechanism.

In mam; buttonhole sewing machines the work-holding means andstitch-forming mechanism not only have a relative feeding movementduring the stitching along the sides of the buttonhole, but after thestitching on the buttonhole has been completed and the stitch-formingmechanism has come to rest, said stitch-forming mechanism andwork-holding means have a further relative movement by which they areshifted relatively from stitching position into buttonhole-cuttingposition, and after the buttonhole slit has been out said parts have anadditional relative movement in the same direction to bring them intostopping position, in which position the machine as a whole is broughtto rest.

In some buttonhole sewing machines the relative shifting movementbetween the stitch-forming mechanism and work-holding means by which theparts are shifted from stitching position to buttonhole-cutting positionand then into stopping position, is one in which the needle has aforward movement relative to the workholding means during the entireshift from stitching position to stopping position, so that when themachine is finally brought to rest the needle is situated somewhat infront of the stitched buttonhole. Under these circumstances the operatorhas to use care in removing the work from the work-holding means afterthe completion of the buttonhole in order to avoid catching the work onthe needle.

As stated aboveitis one of the objects of my present invention toprovide a novel construction wherein when the sewing machine is broughtto rest at the end of the button-hole cycle the relative positionbetween the needle and the work-holding means will be one which is muchmore favorable for removing the work from the work-holding means orplacing it therein without danger of catching the work on the needle,than in buttonhole sewing machines as previously constructed.

In accordance with my invention I provide novel means whereby when thesewing on the buttonhole has been completed the parts are not onlyshifted relatively from stitching position to buttonhole-cuttingposition in the usual manner, but after the buttonhole slit has been cutthe stitch-forming mechanism and work-holding means are given a furtherrelative movement in a reverse direction, or in the direction frombuttonhole-cutting position back toward stitching position, and themachine is brought to rest during this return movement and preferablyjust before such relative movement brings the parts into stitchingposition.

With this arrangement the needle will be protected by the work clampswhen they are raised so that there is very little danger that the workwill be caught on the needle when it is removed from or being introducedinto the work clamps.

In a buttonhole sewing machine embodying this invention the timeinterval required for completing any buttonhole sewing cycle is reducedbecause of the fact that the relative movement between thestitch-forming mechanism and. work-holding means from buttonhole-cuttingposition to stoppingposition is in a direction back toward stitchingposition instead of in a continued forward direction as in priorbuttonhole sewing machines. Because of the fact that with this inventionthe relative movement from buttonhole-cutting position to stoppingposition is part of the relative movement from buttonhole-cuttingposition to stitching position the time required forthe completion of abuttonhole cycle is reduced even though the operation of thestitch-forming mechanism itself is not speeded up. 7 1

In the drawings wherein I have illustrated a selected embodiment of myinvention, Fig. 1 is a side view of a buttonhole sewing machine havingmy improvements incorporated therein;

Fig. 2 is a section on substantially the line 22, Fig. 1;

Fig. 3.15 airagmentary view illustrating the portion 10 of the stitchframe. has the cam groove 14 in its upper face in which the The sewingmachine herein illustrated is ofthat familiar type in which thework-holding means is carried on a work frame. and the stitchformingmechanism is carried on a stitch frame, said frames having a relativefeeding movement during the stitching along the sides of the buttonholeand a further relative movement to carry the parts first from stitchingposition to buttonhole-cutting positionandthen from buttonhole-cuttingposition to stopping position.

The work frame is indicated at l and the work-holding means comprisesthe usual work clamps 2 pivoted to the work frame and co-operating withclamp plates 3 for clamping the work 4 in position. The stitch frame isindicated generally at 5 and it is provided with the usualstitch-forming mechanism which includes a vertically-reciprocatingneedle 6 operating above the work and-suitable looper mechanism or underthread mechanism carried by a turret 8 that is situated beneath the workand which carries the usual throat 9 through which the needle 6operates, said turret being rotatively mounted in the portion 10 of thestitch frame which is situated beneath the work frame 1. The needle 6 iscarried by the usual verticallyreciprocating needle bar 11 which may beoperated in any usual way.

The movement of the'stitch frame on the bed frame or work frameisderived from the usual --main cam 12 which is mounted for rotation ina cam housing 13 that forms part of the under This cam 12 is received astationary follower'15 carried by a stud 16 fixed in and depending fromthe bed frame 1. Since the stud 16 is stationary, rotation of the cam 12will cause the stitch frame to move back andforth in thedirection of thelength of the buttonhole as usual in buttonhole sewing machines of thistype.

The main cam 12 is driven from a worm 17 which meshes with gear teeth onthe periphery of the cam and which is mounted on a shaft 18 journalledin bearings in the stitch frame.-

19 indicates a driving pulley loosely mounted on the shaft 18, and whenthe machine is set in operation at the beginning of the buttonhole cyclethis pulley 19 is clutched to the shaft 18 thereby to start rotativemovement of the main cam. When the stitching on the buttonhole has beencompleted and during the movement of the stitch frame from stitchingposition to buttonhole-cutting position the rotation of the shaft 18 isalso derived from the driving pulley 19 to which it is clutched, thestopping of the machine resulting from unclutching the pulley 19 fromthe shaft 18.

The clutch for clutching the pulley 19 to the main shaft is such as isusually employed in sewing machines of this type and it comprises aclutch dog 20 on the pulley 19 adapted to engage a clutch dog 21 onan'arm 22'fast to the shaft 18. The pulley 19 is'shiftablelongitudinally of the shaft 18 to bring the clutch --dogs--20,--21intoand out ofoperative "engageposition.

lever 32 is normally held inits operative posifront end of the lever 32.

ment and this clutching and unclutching movement is secured through themedium of a lever 22 pivoted at 23 to the cam housing 13 and having anarm 24 connected to a 'collar 25 that is received in a groove formedbetween two flanges 26 on a sleeve that is fast to the pulley 19. Thisconstruction is similar to that'shown in Patent No. 655,637, August 7,1900, or in Patent No. 1,841,133, January 12, 1932.

It should be remarked that while the shaft 18 is driven from the drivingpulley 19 at the beginning and ending of the buttonhole cycle, yet whilethe stitch-forming mechanism is operating to form stitches along thesides of the buttonhole the pulley 19 is disengaged from the shaft 18and the latter is actuated from the shaft 50 which operates thestitch-forming mechanism and which is adapted to be clutched to orunclutched from the driving pulley 51, the construction being such thatwhen the parts have been shifted from buttonhole-cutting position tostitching position the pulley 19 is disconnected from the shaft 18 andthe pulley 51 is clutched to the shaft 50, thereby to start thestitch-forming mechanism in operation and when the sewing on thebuttonhole has been completed, the pulley 51 is unclutched from theshaft 50 and the pulley 19 is again clutched to the shaft 18 thereby tocause the movement of the stitch frame from stitching position tobuttonhole-cutting position. The unclutching of the pulley 19 from theshaft 18 and the clutching of the pulley 51 to the shaft 50 when theparts have moved from buttonhole-cutting opening 29 formed in the arm 30extending from the clutch-controlling lever 22. When the threearmedlever moves clockwise in Fig. 7 such movement will cause the drivingpulley 51 to be clutched to the shaft 50 and the movement of the arm 28will act through the arm 30 of the clutch-controlling lever-to turn thelatter in a direction to disengage the pulley 19 from the shaft 18. Theoperation of this three-armed lever and of the clutches is, the same asthat shown in the above-mentioned patents to which reference may be hadfor a more detailed explanation thereof.

The' clutch-controlling lever 22 is acted on by a spring 31 whichnormally tends to swing it into position to cause the clutch dogs' 20and 21 to be engaged. When the sewing machine is at rest theclutch-controlling lever 22 is retained in its inoperative positionagainst the action of the spring 31 through the medium of a lever 32pivoted at 33 to the under side of the Work frame 1, said lever carryinga stud 34 engaging a cam face 35 on the clutch-controlling lever 22 andholding said lever in its retracted When the machine is at rest thetionshown in Fig. 2 by the starting lever 36 which is pivotally mountedon the Work frame 1 at 53,,said starting lever having 2. dependingextension 3'7 adapted to engage a finger 38-at the acted on by a pushingspring 39 which tends normally to swing it clockwise Fig. 2, Which Thestarting of. the machine is accomplished Said lever 32 isspring,'however,- is less powerful than the spring iii in the usual wayby depressing the starting lever 36 which will remove the end 37 fromengagement with the finger 38. This will unlock the lever 32 and thespring 31 will then act to swing the clutch-controlling lever 22counterclockwise in Fig. 2 thereby clutching the pulley 19 to the shaft18 through the medium of the clutch dogs and 21. This sets the machinein operation and the initial rotation of the cam 12 moves the stitchframe into stitching position. When the stiching position has beenreached the stitch-forming mechanism is set in operation for stitchingalong the sides of the buttonhole, in the manner described in theabove-mentioned patents, during which time the pulley 19 will bedisengaged from the shaft 18 as will be readily understood. When thestitching has been completed the stitch-forming mechanism is brought torest with the needle raised and the pulley 19 is again clutched to theshaft 18 to cause the parts to move from stitching position tobuttonhole-cutting position, in which latter position the buttonholeslit is cut through the medium of the usual buttonhole cutter which isshown as mounted on a cutter arm 41 pivoted to the stitch frame at 42and actuated at the proper time by a cutter cam projection 43 on themain cam 12.

When the stitching on the buttonhole ends the stitch-forming mechanismis in substantially the position shown in Fig. 3 and during the shiftfrom stitching position to buttonhole-cutting position the stitch frameis moved forward to carry the needle somewhat in front of the workclamps as indicated in Fig. 4.

The machines shown in the above-mentioned patents are constructed sothat after the stitch frame has been shifted forwardly from stitchingposition into buttonhole-cutting position and the buttonhole has beencut, said stitch frame is given further forward movement into stoppingposition and the driving pulley 19 is then unclutched from the shaft 18.This is illustrated in Fig. 1.

When the stitching on the buttonhole is completed the position of thestitch frame will he one which will give the needle a position indicatedby the dotted line b in Fig. 1, this being the position at which thestitching on any buttonhole ceases and the position which the needle haswhen the stitching begins on the next buttonhole. The shift of thestitch frame from stitching position to buttonhole-cutting position willcarry the needle from the dotted line position b to the dotted lineposition a. In the prior machines above referred to the additionalmovement of the stitch frame from buttonhole-cutting position tostopping position would carry the needle still further forward into adotted line position indicated at 9 so that when said machines arebrought to rest the needle will be in its extreme forward positionsomewhat in advance of the work clamps. When the machine comes to restthe work clamps are opened so that the operator can remove the work 4 orcan shift the work into position to have a fresh buttonhole sewedtherein. Where the machine stops with the stich-forming mechanism in theadvance position shown by the dotted lines g in Fig. 1 the operator hasto exercise care not to snag the work on the needle as he removes itfrom the clamp or replaces it therein.

In my present invention I have provided means whereby when the sewing onany buttonhole has been completed the stitch frame has its usual forwardshifting movement from stitching position to buttonhole-cutting positionor from the position indicated by the dotted line b Fig. 1 to thatindicated by the dotted line a,

but instead of moving further forwardly into a stopping position afterthe buttonhole has been cut, the stitch frame is started on its reversejourney from the buttonhole-cutting position back toward stitchingposition and the machine is brought to rest during such reverse journeyand with the stitch frame in substantially the full line position Fig. 1or just before it arrives at stitching position. This operation ofmaking the shift from buttonhole-cutting position to stopping positionpart of the return journey from buttonhole-cutting position to stitchingposition is secured partly through the shape of the cam groove 14 andpartly through the medium of a specially-constructed clutch-disengagingcam carried by the clutch-controlling lever 22. The cam groove 14 ismade so as to give the stitch frame not only its feeding movement forsewing along the sides of the buttonhole but also the movement fromstitching position to buttonhole-cutting position and then back tostitching position again.

The specially-constructed clutch-disengaging cam is designed todisconnect the pulley 19 from the shaft 18 at the proper time in thereverse journey from buttonhole-cutting position toward stitchingposition. This cam is in the acted on by a spring 49 which normallytends to turn it into the position shown in Fig. 6.

It will be remembered that the stud 34 is carried by the lever 32 whichis secured to the work frame 1 and hence has no movement in thedirection of the length of the buttonhole,.while the clutch-controllinglever 22 with its cam member 44 are carried by the stitch frame. Duringthe sewing along the sides of the buttonhole the follower 15 isoperating in the portion j of the cam groove 14 and the stud 34 will bein front of the cam 44 as shown in Fig. 5. As the cam 12 continues itsturning movement and the follower 15 passes through the portion 0 of thecamgroove 14, the stitch frame is shifted forward from stitchingposition to buttonholecutting position and during this shifting movementthe stud 34 wipes past the cam 44 and comes into the position shown inFig. 6, the cam yielding or turning about its pivot to allow the stud topass. When the stitch frame reaches the buttonhole-cutting position thefollower 15 enters the concentric portion d of the cam groove and whileit is travelling through said concentric portion the buttonhole slit isout. When the buttonhole slit has been cut the follower enters theportion e of the cam groove 14 and the stitch frame then begins itsreturn'journey from its forward position in which the needle is in theposition shown in Fig. 4 and in the dotted line position a in Fig. 1.starts its return journey the stud 34 engages the cam face 35 of the cam44 thereby shifting the lever 22 downwardly in Fig.2 and disconnectingthe pulley 19 from the shaft 18.

The final disconnection of the pulley from As the stitch frame thusmechanism.

the shaft occurs just before the stitch frame reaches stitching positionso that the machine is brought to rest during the return movement of thestitchframe from buttonhole-cutting position to stitching positionandjust before the stitching position is reached. This is the positionillustrated in full lines in Fig. 1 and it will .be observed that inthis position the needle is protected or guarded by theraised work clamp2 so that the work can be freely removed from the clamps or placedtherein without danger of becoming snagged on the needle.

Another advantage of the construction herein illustrated and which hasbeen referred to above, is that it enables the operator to increase hisproduction without any corresponding increase in the speed of. operationof the stitch-forming It has been explained above. how by means ofthisinvcntion the movement of the stitch frame from buttonhole-cuttingposition forwardly into stopping position (represented by the dottedline position g in Fig. 1) and back to buttonhole-cutting position iseliminated.

In those sewing machines such as illustrated in above-mentioned PatentsNo. 655,63! and No. 1,841,133, when the machine is started in operationthe stitch frame moves from its forward stopping position backwardly tobuttonhole-cutting position and then still further backwardly :t0stitching position, at which time the stitchforming mechanism is set inoperation, and after the stitching on the buttonhole has been completedthe stitch frame moves forwardly from stitching position tobuttonhole-cutting position and subsequently has a further forwardmovement into stopping position. By eliminating this movement frombuttonhole-cutting position forwardly into stopping position and byconstruct- 'ing the sewing machine so that the movement frombuttonhole-cutting position to stopping position is part of the movementnecessary to shift .the stitch frame from its buttonhole-cuttingposition to stitching position, the time interval re-' quired forcompleting the cycle of operations "is'reduced even assuming that thereis no change in the actual speed of operation of the stitchformingmechanism. Therefore, with this invention an operator is able toincrease his production even though there has been no increase in thespeed of operation of the stitch-forming mechanism.

In buttonhole sewing machines of this type the clamps are opened torelease'the work after the buttonhole slit has been cut and in thepresent invention this opening of the clamps occurs while the stitchframe is moving backward from its forward buttonhole-cutting posi- Inremoving the work from the clamps the natural tendency for the operatoris to pull the work forwardly. At the time the clamps are opened,however, the needle is moving backwardly so that the needle and the workhave relative movements in opposite directions and this also helps toprevent the work from becoming caught on the needle.

I claim: '1. A buttonhole sewing machine having stitching mechanism,work-holding means, buttonhole-cutting means, means operating during themaking of each buttonhole to move the stitching mechanism andwork-holding means relatively from stitching position tobuttonholecutting position and back towards stitching position, andmeans to bring the machine to :rest during the relative movement frombuttonholecutting position to stitching position.

2. A buttonhole sewing machine havin stitching mechanism, work-holdingmeans, buttonhole-cutting means, means operating during the making ofeach buttonhole tomove the stitching mechanism relative to thework-holding -means from stitching position to buttonhole-cutting.position and back towards stitching position, and means to bring themachine to rest during the relative movementfrom buttonhole-cuttingposition to stitching position.

3. A buttonhole sewing machine having workholding means, a stitch framecarrying stitching mechanism, means tomove the stitch frame relativelyto the work-holding means to carry said stitch frarnefrom stitchingposition to buttonhole-cutting position and return it, to stitchingposition, a buttonhole cutter to cut the buttonhole slit when the stitchframe is in buttonhole-cutting position, and means to bring the machineto rest during the movement of the stitch frame from buttonhole-cuttingposition to stitching position.

4. A buttonhole sewing machine having workholding means, a stitch framecarrying stitching mechanism, means to move the stitch frame relativelyto the work-holding means to carry said stitch frame from stitchingposition to buttonhole-cutting position and return it to stitchingposition, a buttonhole cutter to cut the buttonhole slit when the stitchframe is in buttonhole-cutting position, and means to bring the machineto rest just before the stitch fram reaches sewing position.

5. A buttonhole sewing machine having workholding means, stitchingmechanism, buttonhole-cutting mechanism, means to give the stitchingmechanism and work-holding means a relative feeding movement duringthese'wing on the buttonhole and a further relative movement at thecompletion of the sewing to carry the parts from sewing position tobuttonholecutting position and back to sewing position,

and means to bring the machine to rest during the relative movement frombuttonhole-cutting position to sewing position.

6. A buttonhole sewing machine having stitching mechanism, work-holdingmeans, means to give the stitching mechanism and work-holding means arelative feeding movement during the sewing on the buttonhole and afterthe stitching is completed a further relative movement first in adirection to separate the stitched buttonhole from the stitchingmechanism and then in a reverse direction, and means to bring themachine to rest during the relative movement in said reverse direction.

7. A buttonhole sewing machine having stitching mechanism, work-holdingmeans, meansto give the stitching mechanism afeeding movement relativetothe work-holding means while sewing along the sides of the buttonholeand after the sewing has been completed a further relative movement.first in a direction to separate the stitched buttonhole from thestitching mechanism and then in an opposite direction, and means tobring the machine to rest during such movement in said oppositedirection.

8. A buttonhole sewing machine having a work frame carrying work-holdingmeans, a stitch frame mounted for movement on the work frame, stitchingmechanism carried by the stitching frame, means to give the stitch framea feeding movement while sewing along the sides of the buttonhole and afurther movement after the sewing is completed, first in a direction toseparate the stitching mechanism from the stitched buttonhole and thenin a reverse direction, and means to bring the machine to rest duringthe movement of the stitch frame in said reverse direction.

9. A buttonhole sewing machine having stitching mechanism, work-holdingmeans, buttonhole-cutting means, means operating between the completionof the stitching on one buttonhole and the beginning of the stitching onthe next buttonhole to move the stitching mechanism and work-holdingmeans from stitching position to buttonhole-cutting position and back tostitching position again, and means to bring the machine to rest duringthe relative movement from buttonhole-cutting position to stitchingposition.

stitch frame from buttonhole-cutting position to stitching position.

11. A buttonhole sewing machine having stitching mechanism, work-holdingmeans and. buttonhole-cutting means, said stitching mechanism andwork-holding means being movable relative to each other and having onerelative position while the buttonhole is being cut and another relativeposition while the stitching mechanism is operating, and means to bringthe machine to rest between buttonhole-cutting position and stitchingposition.

JOSEPH H. PIKUL.

